Stroke: being overweight or obese ups risk
9 April 2010
Australian experts are calling for greater awareness of the link between obesity and stroke, following research showing a progressive increase in stroke risk with increasing weight (Stroke 2010; online first).
People with a body mass index (BMI) of 30 kg/m2 or more face a 64 per cent increased risk of ischaemic stroke (stroke caused by a blockage of the blood vessels supplying the brain) relative to those of normal weight.*
Those with a BMI of 25 to 30 kg/m2 faced a 22 per cent increased risk of ischaemic stroke, the meta-analysis of 2.3 million patients from 25 studies showed. (A meta-analysis is a statistical technique that summarises the results of other studies.)
Professor Geoffrey Donnan, director of the Florey Neuroscience Institute and professor of neurology at the University of Melbourne, said there had previously been little awareness of the relationship between obesity and stroke.
Dr Timothy Kleinig, a neurologist at Royal Adelaide Hospital, agreed that people were probably more aware of the association between obesity and heart disease. “It definitely confirms that obesity is a risk factor for stroke”.
There was also a statistically significant association between obesity, but not overweight, and risk of haemorrhagic stroke (stroke that occurs when a blood vessel in the brain bursts, allowing blood to leak and cause damage to an area of the brain).
* BMI is determined by your weight in kilograms divided by your height in metres squared (kg/m2). A BMI of 18.5 to 24.9 is considered normal weight; 25 to 29.9 is considered overweight; 30 or more is considered obese.
Last Reviewed: 09 April 2010
- 1. Strazzullo P, D'Elia L, Cairella G, et al. Excess body weight and incidence of stroke. Meta-analysis of prospective studies with 2 million participants. Stroke 2010; online first. Abstract available at: http://stroke.ahajournals.org/cgi/content/abstract/STROKEAHA.109.576967v1
2. World Health Organization [website]. BMI classification (last updated 2004). Available at: http://apps.who.int/bmi/index.jsp?introPage=intro_3.html (accessed 2010, Apr 8)
